A golf club head defines a sweet spot typically located centrally on the club face relative to the heel and toe. The sweet spot is defined as the area around the center of mass of a club head that is the most effective part of the face with which to strike a golf ball. The center of mass (or center of the sweet spot) is typically provided along a center line of the club face extending from an upper edge to a lower edge of the club head. It is desirable to strike a golf ball on the sweet spot of the club face in order to impart a straight trajectory to the ball and to better ensure that the ball lands where desired. Mishitting the golf ball near the heel of the club face of a right-handed club results in pivoting the club face leftwardly and, in turn, imparting a leftward trajectory to the ball. Similarly, mishitting the golf ball near the toe of the club face results in pivoting the club face rightwardly and, in turn, imparting a rightward trajectory to the ball.
Golf club heads are known to provide different types of score lines designed to correct the trajectory of mishit golf balls. U.S. Pat. No. 5,505,450 shows a golf club head that has three sets of grooves. Two sets of upwardly directed grooves respectively provided near the toe and heel portions permit corrective spins to a mishit ball in order to straighten the ball trajectory. A center set of horizontal grooves provides spin, but no trajectory correction. A drawback with this type of golf club head is that the ball receives little or no corrective spin from the upwardly directed grooves, unless the face strikes the ball a substantial distance from the center of the face beyond the horizontal grooves toward either the heel or toe.
In response to the foregoing, it is an object of the present invention to provide a golf club head that overcomes the drawbacks and disadvantages of prior art golf club heads.